body {
  margin: 0;
  font-family: 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif;
  background: #f6f8fa;
  min-height: 100vh;
}

nav {
  display: flex;
  justify-content: center;
  align-items: center;
  background: #fff;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  border-radius: 0 0 12px 12px;
  padding: 16px 0 8px 0;
  margin-bottom: 32px;
  gap: 24px;
}

nav a {
  color: #222;
  text-decoration: none;
  font-weight: 500;
  font-size: 18px;
  padding: 6px 18px;
  border-radius: 6px;
  transition: background 0.2s, color 0.2s;
}

nav a:hover {
  background: #e6f0ff;
  color: #1677ff;
}

.logo {
  height: 48px;
  margin: 0 12px;
  vertical-align: middle;
}

.logo.react {
  filter: drop-shadow(0 0 2px #61dafb);
}

.main-card {
  background: #fff;
  border-radius: 16px;
  box-shadow: 0 4px 24px rgba(0,0,0,0.08);
  padding: 32px 40px;
  margin: 0 auto;
  max-width: 420px;
  text-align: center;
}

.card button {
  background: linear-gradient(90deg, #1677ff 0%, #69b1ff 100%);
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 10px 28px;
  font-size: 18px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(22,119,255,0.08);
  transition: background 0.2s, transform 0.1s;
}

.card button:hover {
  background: linear-gradient(90deg, #4096ff 0%, #91caff 100%);
  transform: translateY(-2px) scale(1.04);
}

.read-the-docs {
  color: #888;
  margin-top: 24px;
}

/* 聊天机器人页面样式 */
.chat-root {
  display: flex;
  flex-direction: column;
  height: calc(100vh - 120px);
  /* max-width: 480px; */
  /* padding: 0 24px; */
  margin: 40px auto 0 auto;
  background: #fff;
  border-radius: 16px;
  box-shadow: 0 4px 24px rgba(0,0,0,0.08);
  overflow: hidden;
}

.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 24px 16px 12px 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  background: #f6f8fa;
}

.chat-bubble {
  max-width: 80%;
  padding: 10px 16px;
  border-radius: 16px;
  font-size: 16px;
  line-height: 1.6;
  word-break: break-all;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}

.chat-bubble.user {
  align-self: flex-end;
  background: linear-gradient(90deg, #1677ff 0%, #69b1ff 100%);
  color: #fff;
}

.chat-bubble.bot {
  align-self: flex-start;
  background: #f0f1f3;
  color: #222;
}

.chat-input-container {
  display: flex;
  flex-direction: column;
  border-top: 1px solid #f0f0f0;
}

.chat-input-bar {
  display: flex;
  align-items: center;
  padding: 12px 16px;
  background: #fff;
  gap: 12px;
}

.chat-input-bar:first-child {
  border-bottom: 1px solid #f0f0f0;
}

.chat-input-bar select {
  padding: 10px 14px;
  border-radius: 8px;
  border: 1px solid #e0e0e0;
  font-size: 16px;
  outline: none;
  transition: border 0.2s;
  background-color: white;
}

.chat-input-bar select:focus {
  border: 1.5px solid #1677ff;
}

.chat-input-bar input {
  flex: 1;
  padding: 10px 14px;
  border-radius: 8px;
  border: 1px solid #e0e0e0;
  font-size: 16px;
  outline: none;
  transition: border 0.2s;
}

.chat-input-bar input:focus {
  border: 1.5px solid #1677ff;
}

.chat-input-bar button {
  background: linear-gradient(90deg, #1677ff 0%, #69b1ff 100%);
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 8px 22px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(22,119,255,0.08);
  transition: background 0.2s, transform 0.1s;
}

.chat-input-bar button:hover {
  background: linear-gradient(90deg, #4096ff 0%, #91caff 100%);
  transform: translateY(-2px) scale(1.04);
}

@media (max-width: 600px) {
  .main-card {
    padding: 18px 6px;
    max-width: 98vw;
  }
  nav {
    flex-direction: column;
    gap: 8px;
    padding: 10px 0 4px 0;
  }
  .chat-root {
    max-width: 100vw;
    height: 80vh;
    margin: 0;
    border-radius: 0;
  }
}
